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We present Chandra X-ray results for the jet, nucleus, and gaseous atmosphere ofNGC315, a nearby radio galaxy whose jet kinematics are known through deep radio map-ping. Diffuse X-ray synchrotron emission is detected from the jet out to 30 arcsec from thenucleus, through regions both of fast bulk flow and decelerat ion. The X-ray to radio flux ra-tio drops considerably where the flow decelerates, but the X-ray and radio emissions showsimilar transverse extents throughout, requiring distributed particle acceleration to maintainthe supply of X-ray-emitting electrons. A remarkable knotty filament within the jet is seen inboth the radio and X-ray, contributing roughly 10 per cent ofthe diffuse emission along itsextent at both wavelengths. No completely satisfactory explanation for the filament is found,though its oscillatory appearance, roughly aligned magnetic field, and requirements for par-ticle acceleration, suggest that it is a magnetic strand within a shear layer between fast innerand slower outer flow.Keywords: galaxies:active– galaxies:individual:NGC315– galaxies :jets –radiationmech-anisms: non-thermal – radio continuum: general – X-rays: galaxies

We present an extensive X-ray spectral analysis of the cores of 19 FRII sources in the redshift range 0.5 < z < 1.0 which were selected to be matched in isotropic radio power. The sample consists of 10 radio galaxies and 9 quasars. We compare our results with the expectations from a unification model that ascribes the difference betwee n these two types of sources to the viewing angle to the line of sight, beaming and the presence of a dust and gas torus. We find that the spectrum of all the quasars can be fitted with a sin gle power law, and that the spectral index flattens with decreasing angle to the line of s ight. We interpret this as the effect of increasingly dominant inverse Compton X-ray emission, beamed such that the jet emission outshines other core components. For up to 70 per cent of the radio galaxies we detect intrinsic absorption; their core spectra are best fitted with an unabso rbed steep power law of average spectral index = 2 .1 and an absorbed power law of spectral index = 1 .6, which is flatter than that observed for radio-quiet quasars. We furth er conclude that the presence of a jet affects the spectral properties of absorbed nuclear em ission in AGN. In radio galaxies, any steep-spectrum component of nuclear X-ray emission, similar to that seen in radio-quiet quasars, must be masked by a jet or by jet-related emission.

We present results on the physical states of three high-redshift powerful radio galaxies (3C 292 at z=0.7, 3C 184 at z=1, and 3C322 at z=1.7). They were obtained by combining radio measurements with X-ray measurements from XMM-Newton that separate spectrally and/or spatially radio-related and hot-gas X-ray emission. Originally observed as part of a programme to trace clusters of galaxies at high redshift, none of the sources is found to lie in a rich X-ray-emitting environment similar to those of some powerful radio galaxies at low redshift, although the estimated gas pressures are sufficient to confine the radio lobes. The weak gas emission is a particularly interesting result for 3C 184, where a gravitational arc is seen, suggesting the presence of a very massive cluster. Here Chandra data complement the XMM-Newton measurements in spatially separating X-ray extended emission from that associated with the nucleus and rather small radio source. 3C 292 is the source for which the X-ray-emitting gas is measured with the greatest accuracy, and its temperature of 2 keV and luminosity of 6.5E43 erg/s are both characteristic of a poor cluster. This source allows the most accurate measurement of inverse-Compton X-ray emission associated with the radio lobes. In all structures where the magnetic-field strength can be estimated through combining measurements of radio-synchrotron and inverse-Compton-X-ray emission, the field strengths are consistent with sources being in a state of minimum total energy., Comment: 5 pages, 7 figures. To appear in "X-ray and Radio Connections", eds. Sjouwerman, L.O. & Dyer, K.K. (see http://www.aoc.nrao.edu/events/xraydio/)

We present results from two {\em Chandra}/ACIS-I observations and one {\em XMM-Newton} observation of X-ray emission from the ISM and the inner radio lobes of the nearby radio galaxy Centaurus A. The ISM has an average radial surface brightness profile that is well described by a $\beta$-model profile with index $\beta$=0.40$\pm$0.04 and a temperature of $k_BT_{ISM}\sim$0.29 keV beyond 2 kpc from the nucleus. We find that diffuse X-ray emission is coincident with the outer half of the southwest radio lobe, and a bright X-ray enhancement is detected along the edge of the lobe. On the basis of energetic and lifetime arguments, we reject a nonthermal explanation for this emission. We model this emission as a thin, hot shell or cap of X-ray emitting plasma surrounding the radio lobe that was created by the supersonic inflation of the lobe. This plasma shell is both hotter than ($k_BT_{SH}\sim$2.9 keV) and greatly overpressurized relative to the ambient ISM indicating supersonic expansion. We estimate that the lobe is expanding into the ISM at approximately Mach 8.5 or 2400 km s$^{-1}$. We are not directly observing the bow shock, but rather the cooler, denser material that is accumulating ahead of the contact discontinuity. The thermal energy in the shell is a significant fraction of the thermal energy of the hot ISM, demonstrating the possibility that the hot ISM of early galaxies can be re-energized by outflows from nuclear activity. Interestingly, no similarly bright X-ray emission is detected in or along the edge of the NE lobe, implying that there are differences in the dynamics and evolution of the kpc-scale radio components.

Objectives. Squamous cell carcinoma antigen (SCCA) is a member of the serpin superfamily, and has been used as a serological tumor marker for cervical squamous cell carcinomas. We have identified a closely related serpin gene, leupin (SCCA-2), which may be the fraction previously thought to be the acidic isoform of SCCA. The purpose of this study is to isolate the individual recombinant proteins, to examine their reactivity with current immunological detection methods, and to use a gene-specific method to examine their expression in the uterine cervix. Methods. We have expressed and purified recombinant forms of SCCA and leupin individually. The proteins were characterized with respect to their isoelecric points and their reactivity with the monoclonal antibody from the current tumor marker diagnostic immunoassay (IMx SCC). Reverse transcription polymerase chain reaction (RT-PCR) with gene-specific primers was used to examine expression of both genes. Results. Isoelectric focusing shows that leupin is the more acidic antigen with a determined p I for recombinant leupin (rLeupin) of 6.01, with rSCCA having a p I of 6.17. The IMx SCC monoclonal antibody recognized both rSCCA and rLeupin in immunoassays and immunoblots and both genes are expressed in normal cervix and in cervical carcinoma tissue. Conclusions. The findings from this study suggest that all previous clinical studies examining SCCA expression have used methodology that detects two gene products. The confirmation that leupin or SCCA-2 is the more acidic protein and that its expression is significantly elevated in cervical cancer suggests that this gene product may be the more important tumor marker.

A new structural map of the western Sea of Okhotsk, based on grids of multichannel seismic data, provides several new insights into the Tertiary deformation of Asia, especially in regard to the extension of “extrusion” tectonics, linked to the India-Eurasia collision, into northeastern Asia. The sedimentary basins in this offshore region are the result of two regional shear systems. In the west, the north trending Sakhalin-Hokkaido dextral fault system transects Sakhalin Island. Accessory structures closely related to its dextral shear include northeast trending normal faults as well as northwest trending en echelon folds and thrusts. The accessory normal faults are predominantly Eocene to lower Miocene and indicate transtensional shear, whereas the folds and thrusts are mostly younger and indicate late Miocene and Pliocene transpression. In the north, an east-west trending sinistral shear zone enters the sea at its northwest corner; this sinistral shear system links farther west to extensional faults of the early Tertiary Baikal rift. Extending northeastward from the terminus of this sinistral shear zone are a series of long, predominantly northwest dipping listric normal faults that form a large “lazy-S” shaped pull-apart basin, the Shantar-Liziansky basin (SLB). Normal faults in this 500 × 140 km basin accommodate 15 to 20% extension. Extension and related sinistral shear appear to be largely Eocene to Oligocene in age, with lesser later activity. To the northeast of SLB, a further extension of the sinistral shear zone appears to bend northeastward, transecting Pustorets and Penzhina basins and following the course of the older, Mesozoic Mongol-Okhotsk-Chukotsk active margin and suture; it possibly reaches as far as the Arctic. As suggested by previous workers, the Baikal rift and its associated sinistral shear zone may be interpreted as by-products of the India-Eurasia collision in Eocene time; mapping results included here show that this diffuse sinistral shear system extends much farther to the northeast. The sinistral shear zone is transected by the dextral Sakhalin-Hokkaido fault zone in the Kashevarov region of central SLB, where a fan of north to northwest striking late Tertiary transpressional fault splays marks the northern termination of the dextral fault zone. Older SLB normal faults are locally deformed, and half grabens are partly inverted, by the slightly younger dextral splays. The two regional fault systems are essentially conjugate, and the pattern of intersection closely resembles that predicted by recent modelling studies of India/Eurasia collision tectonics.

The emission mechanisms in extragalactic jets include synchrotron and various inverse-Compton processes. At low (radio through infrared) energies, it is widely agreed that synchrotron emission dominates in both low-power (FR I) and high-power (FR II and quasar) jets, because of the power-law nature of the spectra observed and high polarizations. However, at higher energies, the emission mechanism for high-power jets at kpc scales is hotly debated. Two mechanisms have been proposed: either inverse-Compton of cosmic microwave background photons or synchrotron emission from a second, high-energy population of electrons. Here we discuss optical polarimetry as a method for diagnosing the mechanism for the high-energy emission in quasar jets, as well as revealing the jet's three-dimensional energetic and magnetic field structure. We then discuss high-energy emission mechanisms for powerful jets in the light of the HST polarimetry of PKS 1136-135., 4 pages, 1 figure. To appear in proceedings of "The Monster's Fiery Breath: Feedback in galaxies, groups, and clusters" meeting, June 1-5, 2009 held in Madison, WI, USA

Clues to the X-ray emission mechanisms in flat radio spectrum AGNs arise from comparing radio, optical, and X-ray luminosities for a sample of 80 known-redshift radio-selected AGNs for which the radio luminosity is dominated by flat-spectrum compact-core emission. The X-ray spectral luminosity lies on average above an extrapolation from lower frequencies for all the QSOs, despite a range in optical polarization and activity. Such an X-ray “excess” is often interpreted as support for the presence of a Compton-scattered component. In contrast, for the BL Lac objects, the X-ray spectral luminosity on average lies on the extrapolation from lower frequencies. This is particularly interesting in view of evidence that the X-ray emission of BL Lac objects may be unbeamed while the radio emission is beamed. If the 80 sample sources are assumed to be preferentially beamed towards the observer in radio emission, because of their radio selection, a test supports the X-ray emission also being beamed. However, the BL Lac sub-sample is too small for the test to be applied to it alone.

Over the last few years, high-quality X-ray imaging and spectroscopic data from Chandra and XMM-Newton have added greatly to the understanding of the physics of radio jets, Here we describe the current state of knowledge with an emphasis on the underlying physics used to interpret multiwavelength data in terms of physical parameters.

This paper describes the performance of XMM-Newton for serendipitous surveys and summarises the scope and potential of the XMM-Newton Serendipitous Survey. The role of the Survey Science Centre (SSC) in the XMM-Newton project is outlined. The SSC's follow-up and identification programme for the XMM-Newton serendipitous survey is described together with the presentation of some of the first results., 9 pages, 4 figs, accepted for A&A Letters, XMM issue, version with higher resolution figs available from http://xmmssc-www.star.le.ac.uk/papers

The serpin superfamily of proteins has expanded rapidly in recent years as represented by the ovalbumin-type serpin subfamily. PCR methods have been used to identify new ovalbumin-type serpins, including leupin or SCCA-2, a close relative of SCCA. Although in vitro inhibition of proteases by these serpins has been shown, and we have evidence that leupin can protect cells against apoptosis, the exact role of these serpins is not well understood. Finding relevant targets is a major challenge in serpin biology, and we have investigated the yeast-2-hybrid trap for identification of new interactions. Preliminary studies suggest that serpins are at the upper limit for bait size, but this technique may be useful for identifying interactions where full-length serpin protein is not required.

Using ROSAT observations, we estimate gas pressures in the X-ray-emitting medium surrounding 63 FRII radio galaxies and quasars. We compare these pressures with the internal pressures of the radio-emitting plasma estimated by assuming minimum energy or equipartition. In the majority of cases (including 12/13 sources with modelled, spatially resolved X-ray emission) radio sources appear to be underpressured with respect to the external medium, suggesting that simple minimum-energy arguments underestimate the sources' internal energy density. We discuss possible departures from the minimum energy condition and the consequences of our result for models of the dynamics of radio galaxies, in particular self-similar models (Kaiser & Alexander 1997)., 11 pages, 4 figures, accepted for MNRAS

Ovalbumin is a non-inhibitory serpin which lacks the ability to undergo the S --R transition or conformational change. Amino acid residues in the hinge region (P11 to P14) of ovalbumin and other non-inhibitory serpins differ from the concensus sequence of this region of inhibitory serpins, and have been proposed to be responsible for lack of inhibitory properties, particularly the P14 charged residue. Site directed mutagenesis using PCR overlap extension was performed on these residues in ovalbumin to create a mutant with three amino acid changes, R340T, V342A and V343A. However analysis of the mutant recombinant ovalbumin with the consensus residues failed to show inhibitory activity or decreased stability, indicating that the hinge region alone is not responsible for lack of inhibition. A series of three fusion proteins were then constructed by replacing varying C-terminal regions of ovalbumin with the corresponding region of the inhibitory ov-serpin PAI-2 in order to further analyse serpin inhibitory function. Fusion proteins F1 and F2 contained approximately 16% and 35% PAI-2, respectively. This resulted in the replacing of structural features such as the reactive site loop, hinge region and beta sheet strands 5A and 6A. However both fusion proteins showed no inhibitory activity with the PAI-2 target protease urokinase (uPA) and no decrease in stability as analysed by transverse urea gradient (TUG) gels. The third chimeric fusion protein constructed (F3) contained 64% PAI-2 and did demonstrate inhibition of uPA, SDS-PAGE stable complex formation with uPA and increased instability on TUG gels. Structural differences between the inactive F2 and active F3 include the replacement of helix F and beta sheet strand 3A of ovalbumin with those of PAI-2, suggesting that these features may have a key role in serpin beta-sheet opening and inhibitory function.

We present 18 GHz Australia Telescope Compact Array imaging of the Mpc-scale quasar jet PKS 0637-752 with angular resolution ~0.58 arcseconds. We draw attention to a spectacular train of quasi-periodic knots along the inner 11 arcseconds of the jet, with average separation ~1.1 arcsec (7.6 kpc projected). We consider two classes of model to explain the periodic knots: those that involve a static pattern through which the jet plasma travels (e.g. stationary shocks); and those that involve modulation of the jet engine. Interpreting the knots as re-confinement shocks implies the jet kinetic power Q ~ 10^{46} erg/s, but the constant knot separation along the jet is not expected in a realistic external density profile. For models involving modulation of the jet engine, we find that the required modulation period is 2 x 10^3 yr < \tau < 3 x 10^5 yr. The lower end of this range is applicable if the jet remains highly relativistic on kpc-scales, as implied by the IC/CMB model of jet X-ray emission. We suggest that the quasi-periodic jet structure in PKS 0637-752 may be analogous to the quasi-periodic jet modulation seen in the microquasar GRS 1915+105, believed to result from limit cycle behaviour in an unstable accretion disk. If variations in the accretion rate are driven by a binary black hole, the predicted orbital radius is 0.7 < a < 30 pc, which corresponds to a maximum angular separation of ~0.1 - 5 mas.

One of ROSAT’s major achievements has been its ability to separate X‐ray emission components in many radio galaxies, where this was previously possible only for a very few well‐known sources, e.g.,M87 and Cen A. The dominant X‐ray emission mechanism in radio galaxies as a class was unclear, with correlations between the X‐ray and radio emissions used on one hand to argue for a nuclear origin for the X‐rays, and on the other hand for a thermal origin. Now, with ROSAT we find the presence of both resolved (thermal) and unresolved emission to be typical.Our results are illustrated with PSPC data from the first six radio galaxies in our study. Spectral and spatial measurements independently support the presence of multiple emission components. The resolved emission can be modeled as thermal radiation from gas of galaxy, group, or cluster dimension depending on object. The unresolved emission may be thermal or nonthermal. Evidence is presented to support a nonthermal origin for most of the unresolved emission:...

The ROSAT PSPC spectrum of NGC 6251 can be fitted with either a multiple‐component model obscured by the gas column within our Galaxy or by a single power‐law component obscured by this Galactic gas and an additional column N=1.3×1021 cm−2. We have used the VLA to search for the the HI line in absorption towards the radio core of NGC 6251 to set limits on the total X‐ray absorbing column. We find marginal evidence for a weak, broad, absorption feature associated with NGC 6251 which could provide the extra HI column suggested by the simpler X‐ray spectral fit.

A correlation of the form , with γ = 0.83, is found between 2 keV monochromatic X-ray luminosity and 1.65 μm monochromatic infrared luminosity for a sample of optically selected radio-quiet QSOs. This is equivalent to an average 1.65 μm to 2 keV spectral index of αir/x = 1.28+0.05 log(lir/1031 ergs s−1 Hz−1). The ratio of X-ray to infrared luminosity decreases with increasing infrared luminosity in a manner similar to the relationship between X-ray and optical luminosity. The standard deviations of the distributions of data about the best-fit functions are comparable for the X-ray versus infrared and X-ray versus optical fits. Thus, contrary to a previous claim, the infrared luminosity is not better than the optical luminosity at predicting the X-ray emission from QSOs.

Pantetheine phosphate adenylyltransferase (EC 2.7.7.3) and dephospho-CoA kinase (EC 2.7.1.24) were purified to near homogeneity from pig liver. The purification steps included the use of Sepharose-linked triazine dyes and affinity elution by CoA. Both activities co-purified at every stage of the 18 000-fold purification. An Mr of 115 000 was obtained by gel filtration on Sephadex G-150, and the final preparation yielded one major band on sodium dodecyl sulphate/polyacrylamide-gel electrophoresis, with a subunit Mr of 57 000. It is concluded that pantetheine phosphate adenylyltransferase and dephospho-CoA kinase exist as a bifunctional dimeric protein, which could be designated CoA synthetase.

Culture conditions affecting the formation of beta-galactosidase inclusion bodies in E. coli were examined. High temperature, early induction, high salt concentration and low aeration were all found to favour an increase of insoluble beta-galactosidase and the formation of visible inclusion bodies. The ratio of soluble to insoluble beta-galactosidase decreased during the course of cell growth. When assayed for beta-galactosidase activity, the inclusion bodies were enzymatically active with a specific activity of one third that of soluble beta-galactosidase. The activity remained associated with the inclusion bodies on washing with detergent and high ionic strength buffers. These results suggest that inclusion bodies can contain correctly folded protein.

The Advanced X-ray Astrophysics Facility (AXAF) will be a 15-year lifetime observatory, intended to investigate the nature of celestial objects and physical processes, and to study the history and evolution of the universe. We are investigating how to translate the requirements for scientific measurements (e.g., fluxes, spectra and sizes of sources) into operational requirements for the calibration of the AXAF X-ray mirrors and scientific instruments. We carry out a complete simulation of the process of acquiring data from an X-ray source, and analyze the data using various calibration errors. We generate an ideal spectrum of an X-ray source and convolve it with hypothetical "true" mirror and instrument responses to simulate an expected spectrum. This spectrum may be randomized, independently, a large number of times to simulate the effects of photon statistics. These data are analyzed as if they were actual flight data. We introduce controlled perturbations in the mirror and instrument responses used in the analysis. Such perturbations may include: the neglect of extended X-ray absorption fine structure (EXAFS), errors in the jump of absorption coefficients across atomic shell energies, changes in the optical constants of mirror coatings, effects of dust contamination, or arbitrary calibration measurement errors. We perform x2 fits, and assess the changes in the fitted results from those resulting when the data are analyzed with the "true" mirror and instrument responses. In this paper we discuss an initial study of exponential energy spectra with galactic absorption. We assume perfect detector response and consider only the effects of errors in the on-axis effective area of the mirror.

Our statistical study finds that the X-ray luminosity, lx for an average QSO of given optical luminosity, lo is an increasing function of radio luminosity, lr. An average QSO of given lo and lr has higher lx if the radio spectrum is flat than if it is steep. The correlation between lx, lo and lr appears to be improved if lr refers only to core emission, lrcore. Assuming an average radio-loud QSO is a radio-quiet QSO with a separate component which produces lrcore and Ixcore, lxcore/lrcore is larger if the core is that of a QSO with extended radio structure than if that of a compact flat-spectrum QSO.

The hypothesis that normal galaxies are on the average more luminous in the X-ray region than the Milky Way galaxy or M31 and therefore are possible candidates for the low-luminosity sources of the 2 to 60 keV extragalactic diffuse background is tested. Data from the A-2 detectors on the HEAO-1 spacecraft were examined for emission from positions coincident with 76 selected normal galaxies, and upper limits to the average galactic luminosity for various luminosity distributions resulting in the observed count rate distribution were determined. For uniform and exponential galactic luminosity distributions, limits of 2.7 x 10 to the 38th erg/sec and 3.4 x 10 to the 38th erg/sec, respectively, at the 90% confidence level were obtained. It is shown that the Hubble-constant-independent upper limit to galactic emissivity is less than 1% of the diffuse background emissivity, indicating that normal galaxies are not responsible for the diffuse X-ray background and have luminosities comparable to that of the Galaxy.

Proportional counters on the OsO-8 spacecraft measured the X-ray spectrum of QSR 0241+622 in the range 2-50 keV. The best power law fit has a proton spectral index and 90 percent errors gamma = 1.93 (+0.5, -0.3) and low energy absorption consistent with reported gas column densities, but a thermal bremsstrahlung form with temperature 13.1 keV cannot be excluded. No indication of spectral variability is found in three observations of the source with HEAO-A2, although a possible 15-30 percent intensity change over a period of 6 months was observed. The quasar is similar to 3C 273 in the proportion of energy emitted in various bands, excluding the radio, if reported radiation above 50 keV from its direction is indeed associated with QSO 0241+622. The two quasars are compared and possible energy generation scenarios are discussed. Implications concerning quasar contributions to the diffuse background are discussed.

Quasi-simultaneous observations of the BL Lac object Mrk 501 were performed for the first time at X-ray, ultraviolet, visible infrared, and radio frequencies. As the BL Lac objects are known to vary in their flux, such a "quasi-instantaneous" spectral energy profile is necessary in order to describe properly the energy generation mechanism. The observed spectral slope from the X-ray to UV regions is positive and continuous, but that from the mid-UV to visible light region becomes gradually flat and possibly turns down toward lower frequencies; the optical-radio emission cannot be accounted for by a single power law. Several theoretical models have been considered for the emission mechanism. In some cases quantitative comparison with the data is not practical. However, most of the models are, at least, not inconsistent with the observations. A quantitative comparison has been performed with the synchroton self-Compton model; the total spectrum is found consistent with this model. The spectrum from visible light to X-ray is consistent with synchrotron radiation or with inverse-Compton scattering by a hot thermal cloud of electrons. The continuity of the spectral slope from X-ray to UV implied by the current data suggests that the previous estimates of the total luminosity of this BL Lac object has been underestimated by a factor of about 3 or 4.

A sample of 25 QSOs was used to investigate the average spectrum between the soft X-ray energy band of the Einstein Observatory image proportional counter, and the higher energy band of the HEAO 1 A2 experiment. The spectrum is similar to thoe exhibited by Seyfert galaxies and narrow emission line galaxies above 2 keV. The spectrum is soft enough that if these objects are typical of the higher redshift, more radio-quiet QSOs, then it is possible to exclude QSOs as being the dominant origin of the diffuse X-ray background.

The HEAO A2 experiment data was systematically searched for unresolved galactic disc emission. Although there were suggestions of non-uniformities in the emission, the data were consistent with a disc of half-thickness 241 + 22 pc and surface emissivity (2-10 keV) at galactic radius R(kpc) of 2.2 10 to the minus 7th power exp(-R/3.5) erg/sq cm to the (-2)power/s (R 7.8 kpc). giving a luminosity of approximately 4.4 10 to the 37th power erg S to the (-1) power. If the model is extrapolated to radii less than 7.8 kpc, the unresolved disc emission is approximately 1.4 10 to the 38th power erg S to the (-1) power (2-10 keV) i.e., a few percent of the luminosity of the galaxy in resolved sources. the disc emission has a spectrum which is significantly softer than that of the high galactic latitude diffuse X-ray background and it is most probably of discrete source origin.

An X-ray spectral measurement of the quasar 3C 273 with the HEAO-A2 experiment in June/July 1978 is reported. The best power law fit to the photon flux over the range 2-60 keV gives a slope of 1.41 + or - 0.02. However, structure is observed, indicating a slope of 1.52 between 2 keV and 9 keV and a slight flattening between 9 keV and 30 keV. Observations with the same experiment in December 1977 and OSO-8 in June 1976 allows confirmation of 40% intensity variability on the time scale of months, although within limits provided by the poorer statistical quality of the additional data no spectral change is discerned. Absorption from the source is found to be low, with the 1978 data yielding a 90% confidence upper limit to the hydrogen column density of 4.5 x 10 to the 21st power atoms/sq cm.

In the present study, the region of the gamma 195 + 5 was searched for X-ray emission to a level of approximately 10 to the minus eleventh erg/sq cm-sec. A source is detected whose position is in agreement with the position of the gamma-ray source. The area of the X-ray box is approximately five times smaller than the estimated gamma-ray error region; it will guide further observations at X-ray and other wavelengths. The probability that the source is located by chance within the gamma-ray error region is estimated at 9%. The X-ray spectrum appears to be too steep to extrapolate simply toward the 100 MeV point.